docs(router): Added section for named outlets and secondary routes (#2842)

public/docs/_examples/router/e2e-spec.ts

@@ -28,21 +28,25 @@ describe('Router', function () {
 
       adminHref: hrefEles.get(2),
       adminPreloadList: element.all(by.css('my-app > ng-component > ng-component > ul > li')),
+      
       loginHref: hrefEles.get(3),
       loginButton: element.all(by.css('my-app > ng-component > p > button')),
       
-      sidekicksButton: element.all(by.css('my-app > ng-component > button')),
+      contactHref: hrefEles.get(4),
+      contactCancelButton: element.all(by.buttonText('Cancel')),
       
+      outletComponents: element.all(by.css('my-app > ng-component'))
     };
   }
 
   it('should be able to see the start screen', function () {
     let page = getPageStruct();
-    expect(page.hrefs.count()).toEqual(4, 'should be 4 dashboard choices');
+    expect(page.hrefs.count()).toEqual(5, 'should be 5 dashboard choices');
     expect(page.crisisHref.getText()).toEqual('Crisis Center');
     expect(page.heroesHref.getText()).toEqual('Heroes');
     expect(page.adminHref.getText()).toEqual('Admin');
     expect(page.loginHref.getText()).toEqual('Login');
+    expect(page.contactHref.getText()).toEqual('Contact');
   });
 
   it('should be able to see crises center items', function () {
@@ -120,12 +124,12 @@ describe('Router', function () {
     });
   });
 
-  it('should be able to handle 404 pages', function () {
+  it('should be able to see the secondary route', function () {
     let page = getPageStruct();
     page.heroesHref.click().then(function() {
-      return page.sidekicksButton.click();
+      return page.contactHref.click();
     }).then(function() {
-      expect(page.routerTitle.getText()).toContain('Page Not Found');
+      expect(page.outletComponents.count()).toBe(2, 'should be 2 displayed routes');
     });
   });
 

public/docs/_examples/router/ts/app/app-routing.module.3.ts

@@ -1,11 +1,17 @@
 // #docplaster
-// #docregion
+// #docregion , v3
-import { NgModule }             from '@angular/core';
+import { NgModule }     from '@angular/core';
 import { RouterModule, Routes } from '@angular/router';
-import { PageNotFoundComponent }from './not-found.component';
+import { ComposeMessageComponent } from './compose-message.component';
 
 const appRoutes: Routes = [
-  { path: '**', component: PageNotFoundComponent }
+// #enddocregion v3
+  {
+    path: 'compose',
+    component: ComposeMessageComponent,
+    outlet: 'modal'
+  }
+// #docregion v3
 ];
 
 @NgModule({

public/docs/_examples/router/ts/app/app-routing.module.4.ts

@@ -1,13 +1,17 @@
-// #docplaster
 // #docregion
 import { NgModule }             from '@angular/core';
 import { RouterModule, Routes } from '@angular/router';
 import { PageNotFoundComponent }from './not-found.component';
 
-import { CanDeactivateGuard } from './can-deactivate-guard.service';
+import { ComposeMessageComponent }  from './compose-message.component';
+import { CanDeactivateGuard }       from './can-deactivate-guard.service';
 
 const appRoutes: Routes = [
-  { path: '**', component: PageNotFoundComponent }
+  {
+    path: 'compose',
+    component: ComposeMessageComponent,
+    outlet: 'modal'
+  }
 ];
 
 @NgModule({

public/docs/_examples/router/ts/app/app-routing.module.5.ts

@@ -4,15 +4,21 @@ import { NgModule }     from '@angular/core';
 // #docregion import-router
 import { RouterModule, Routes } from '@angular/router';
 // #enddocregion import-router
-import { PageNotFoundComponent }  from './not-found.component';
+
-import { CanDeactivateGuard }     from './can-deactivate-guard.service';
+import { ComposeMessageComponent } from './compose-message.component';
+import { CanDeactivateGuard }      from './can-deactivate-guard.service';
 // #docregion can-load-guard
-import { AuthGuard }          from './auth-guard.service';
+import { AuthGuard }               from './auth-guard.service';
 // #enddocregion can-load-guard
 
 // #docregion lazy-load-admin, can-load-guard
 
 const appRoutes: Routes = [
+  {
+    path: 'compose',
+    component: ComposeMessageComponent,
+    outlet: 'modal'
+  },
   {
     path: 'admin',
     loadChildren: 'app/admin/admin.module#AdminModule',

public/docs/_examples/router/ts/app/app-routing.module.6.ts

@@ -8,11 +8,16 @@ import {
 // #docregion preload-v1
 } from '@angular/router';
 
-import { PageNotFoundComponent }  from './not-found.component';
+import { ComposeMessageComponent } from './compose-message.component';
-import { CanDeactivateGuard }     from './can-deactivate-guard.service';
+import { CanDeactivateGuard }      from './can-deactivate-guard.service';
-import { AuthGuard }              from './auth-guard.service';
+import { AuthGuard }               from './auth-guard.service';
 
 const appRoutes: Routes = [
+  {
+    path: 'compose',
+    component: ComposeMessageComponent,
+    outlet: 'modal'
+  },
   {
     path: 'admin',
     loadChildren: 'app/admin/admin.module#AdminModule',

public/docs/_examples/router/ts/app/app-routing.module.ts

@@ -3,12 +3,17 @@
 import { NgModule }             from '@angular/core';
 import { RouterModule, Routes } from '@angular/router';
 
-import { PageNotFoundComponent }  from './not-found.component';
+import { ComposeMessageComponent }  from './compose-message.component';
-import { CanDeactivateGuard }     from './can-deactivate-guard.service';
+import { CanDeactivateGuard }       from './can-deactivate-guard.service';
-import { AuthGuard }              from './auth-guard.service';
+import { AuthGuard }                from './auth-guard.service';
-import { PreloadSelectedModules } from './selective-preload-strategy';
+import { PreloadSelectedModules }   from './selective-preload-strategy';
 
 const appRoutes: Routes = [
+  {
+    path: 'compose',
+    component: ComposeMessageComponent,
+    outlet: 'modal'
+  },
   {
     path: 'admin',
     loadChildren: 'app/admin/admin.module#AdminModule',
@@ -26,10 +31,6 @@ const appRoutes: Routes = [
     data: {
       preload: true
     }
-  },
-  {
-    path: '**',
-    component: PageNotFoundComponent
   }
   // #enddocregion preload-v2
 ];

public/docs/_examples/router/ts/app/app.component.4.ts

@@ -12,6 +12,9 @@ import { Component } from '@angular/core';
       <a routerLink="/admin" routerLinkActive="active">Admin</a>
     </nav>
     <router-outlet></router-outlet>
+  // #enddocregion template
+    <router-outlet name="modal"></router-outlet>
+  // #enddocregion template    
   `
   // #enddocregion template
 })

public/docs/_examples/router/ts/app/app.component.ts

@@ -12,8 +12,10 @@ import { Component } from '@angular/core';
       <a routerLink="/heroes" routerLinkActive="active">Heroes</a>
       <a routerLink="/admin" routerLinkActive="active">Admin</a>
       <a routerLink="/login" routerLinkActive="active">Login</a>
+      <a [routerLink]="[{ outlets: { modal: ['compose'] } }]">Contact</a>
     </nav>
     <router-outlet></router-outlet>
+    <router-outlet name="modal"></router-outlet>
   `
   // #enddocregion template
 })

public/docs/_examples/router/ts/app/app.module.4.ts

@@ -5,19 +5,19 @@ import { NgModule }       from '@angular/core';
 import { CommonModule }   from '@angular/common';
 import { FormsModule }    from '@angular/forms';
 
-import { AppComponent }         from './app.component';
+import { AppComponent }            from './app.component';
-import { PageNotFoundComponent }from './not-found.component';
+import { PageNotFoundComponent }   from './not-found.component';
-import { AppRoutingModule }     from './app-routing.module';
+import { AppRoutingModule }        from './app-routing.module';
-
+import { HeroesModule }            from './heroes/heroes.module';
-import { HeroesModule }           from './heroes/heroes.module';
 // #docregion crisis-center-module
-import { CrisisCenterModule }     from './crisis-center/crisis-center.module';
+import { CrisisCenterModule }      from './crisis-center/crisis-center.module';
 // #enddocregion crisis-center-module
+import { ComposeMessageComponent } from './compose-message.component';
 // #docregion admin-module
-import { AdminModule }            from './admin/admin.module';
+import { AdminModule }             from './admin/admin.module';
 // #docregion crisis-center-module
 
-import { DialogService }          from './dialog.service';
+import { DialogService }           from './dialog.service';
 
 @NgModule({
   imports: [
@@ -26,13 +26,16 @@ import { DialogService }          from './dialog.service';
     HeroesModule,
     CrisisCenterModule,
 // #enddocregion crisis-center-module
+// #enddocregion admin-module
     AdminModule,
 // #docregion crisis-center-module
     AppRoutingModule
   ],
   declarations: [
     AppComponent,
-    PageNotFoundComponent
+// #enddocregion admin-module, crisis-center-module
+    ComposeMessageComponent
+// #docregion admin-module, crisis-center-module
   ],
   providers: [
     DialogService

public/docs/_examples/router/ts/app/app.module.5.ts

@@ -1,21 +1,22 @@
+// #docplaster
 // #docregion
 import { NgModule }       from '@angular/core';
-import { BrowserModule }  from '@angular/platform-browser';
+import { CommonModule }   from '@angular/common';
 import { FormsModule }    from '@angular/forms';
 
-import { AppComponent }         from './app.component';
+import { AppComponent }            from './app.component';
-import { PageNotFoundComponent }from './not-found.component';
+import { AppRoutingModule }        from './app-routing.module';
-import { AppRoutingModule }     from './app-routing.module';
 
-import { HeroesModule }        from './heroes/heroes.module';
+import { HeroesModule }            from './heroes/heroes.module';
-import { CrisisCenterModule }  from './crisis-center/crisis-center.module';
+import { CrisisCenterModule }      from './crisis-center/crisis-center.module';
-import { AdminModule }         from './admin/admin.module';
+import { ComposeMessageComponent } from './compose-message.component';
 
-import { DialogService }       from './dialog.service';
+import { AdminModule }             from './admin/admin.module';
+import { DialogService }           from './dialog.service';
 
 @NgModule({
   imports: [
-    BrowserModule,
+    CommonModule,
     FormsModule,
     HeroesModule,
     CrisisCenterModule,
@@ -24,7 +25,7 @@ import { DialogService }       from './dialog.service';
   ],
   declarations: [
     AppComponent,
-    PageNotFoundComponent
+    ComposeMessageComponent
   ],
   providers: [
     DialogService
@@ -33,3 +34,4 @@ import { DialogService }       from './dialog.service';
 })
 export class AppModule {
 }
+// #enddocregion

public/docs/_examples/router/ts/app/app.module.7.ts

@@ -7,8 +7,10 @@ import { AppComponent }         from './app.component';
 import { PageNotFoundComponent }from './not-found.component';
 import { AppRoutingModule }     from './app-routing.module';
 
-import { HeroesModule }        from './heroes/heroes.module';
+import { HeroesModule }            from './heroes/heroes.module';
-import { CrisisCenterModule }  from './crisis-center/crisis-center.module';
+import { CrisisCenterModule }      from './crisis-center/crisis-center.module';
+import { ComposeMessageComponent } from './compose-message.component';
+
 import { LoginRoutingModule }  from './login-routing.module';
 import { LoginComponent }       from './login.component';
 
@@ -25,7 +27,7 @@ import { DialogService }       from './dialog.service';
   ],
   declarations: [
     AppComponent,
-    PageNotFoundComponent,
+    ComposeMessageComponent,
     LoginComponent
   ],
   providers: [

public/docs/_examples/router/ts/app/app.module.ts

@@ -7,9 +7,10 @@ import { AppComponent }         from './app.component';
 import { PageNotFoundComponent } from './not-found.component';
 import { AppRoutingModule }     from './app-routing.module';
 
-import { HeroesModule }         from './heroes/heroes.module';
+import { HeroesModule }             from './heroes/heroes.module';
-import { LoginRoutingModule }   from './login-routing.module';
+import { ComposeMessageComponent }  from './compose-message.component';
-import { LoginComponent }       from './login.component';
+import { LoginRoutingModule }       from './login-routing.module';
+import { LoginComponent }           from './login.component';
 
 import { DialogService }        from './dialog.service';
 
@@ -23,7 +24,7 @@ import { DialogService }        from './dialog.service';
   ],
   declarations: [
     AppComponent,
-    PageNotFoundComponent,
+    ComposeMessageComponent,
     LoginComponent
   ],
   providers: [

public/docs/_examples/router/ts/app/compose-message.component.1.ts

@@ -0,0 +1,108 @@
+// #docplaster
+// #docregion
+// #docregion v1
+import 'rxjs/add/observable/of';
+import 'rxjs/add/operator/delay';
+import 'rxjs/add/operator/do';
+import { Component, HostBinding,
+         trigger, transition,
+         animate, style, state }  from '@angular/core';
+import { Router } from '@angular/router';
+
+import { Observable } from 'rxjs/Observable';
+
+@Component({
+  template: `
+    <h3>Contact Crisis Center</h3>
+    <div *ngIf="details">
+      {{ details }}
+    </div>
+    <div>
+      <div>
+        <label>Message: </label>
+      </div>
+      <div>
+        <textarea [(ngModel)]="message" rows="10" cols="35" [disabled]="sending"></textarea>
+      </div>
+    </div>
+    <p *ngIf="!sending">
+      <button (click)="send()">Send</button>
+// #enddocregion v1
+      <button (click)="cancel()">Cancel</button>
+// #docregion v1
+    </p>
+  `,
+  styles: [
+    `
+      :host {
+        position: relative;
+        bottom: 10%;
+      }
+    `
+  ],
+  animations: [
+    trigger('routeAnimation', [
+      state('*',
+        style({
+          opacity: 1,
+          transform: 'translateX(0)'
+        })
+      ),
+      transition(':enter', [
+        style({
+          opacity: 0,
+          transform: 'translateY(100%)'
+        }),
+        animate('0.2s ease-in')
+      ]),
+      transition(':leave', [
+        animate('0.5s ease-out', style({
+          opacity: 0,
+          transform: 'translateY(100%)'
+        }))
+      ])
+    ])
+  ]
+})
+export class ComposeMessageComponent {
+  @HostBinding('@routeAnimation') get routeAnimation() {
+    return true;
+  }
+
+  @HostBinding('style.display') get display() {
+    return 'block';
+  }
+
+  @HostBinding('style.position') get position() {
+    return 'absolute';
+  }
+
+  details: string;
+  sending: boolean = false;
+
+  constructor(private router: Router) {}
+
+  send() {
+    this.sending = true;
+    this.details = 'Sending Message...';
+
+    Observable.of(true)
+      .delay(1000)
+      .do(() => {
+        this.sending = false;
+// #enddocregion v1
+        this.closeModal();
+// #docregion v1
+      }).subscribe();
+  }
+
+// #enddocregion v1
+  closeModal() {
+    this.router.navigate(['/', { outlets: { modal: null }}]);
+  }
+
+  cancel() {
+    this.closeModal();
+  }
+}
+// #enddocregion

public/docs/_examples/router/ts/app/compose-message.component.ts

@@ -0,0 +1,105 @@
+// #docregion
+import 'rxjs/add/observable/of';
+import 'rxjs/add/operator/delay';
+import 'rxjs/add/operator/do';
+import { Component, HostBinding,
+         trigger, transition,
+         animate, style, state }  from '@angular/core';
+import { Router } from '@angular/router';
+
+import { Observable } from 'rxjs/Observable';
+
+@Component({
+  template: `
+    <h3>Contact Crisis Center</h3>
+    <div *ngIf="details">
+      {{ details }}
+    </div>
+    <div>
+      <div>
+        <label>Message: </label>
+      </div>
+      <div>
+        <textarea [(ngModel)]="message" rows="10" cols="35" [disabled]="sending"></textarea>
+      </div>
+    </div>
+    <p *ngIf="!sending">
+      <button (click)="send()">Send</button>
+      <button (click)="cancel()">Cancel</button>
+    </p>
+  `,
+  styles: [
+    `
+      :host {
+        position: relative;
+        bottom: 10%;
+      }
+    `
+  ],
+  animations: [
+    trigger('routeAnimation', [
+      state('*',
+        style({
+          opacity: 1,
+          transform: 'translateX(0)'
+        })
+      ),
+      transition(':enter', [
+        style({
+          opacity: 0,
+          transform: 'translateY(100%)'
+        }),
+        animate('0.2s ease-in')
+      ]),
+      transition(':leave', [
+        animate('0.5s ease-out', style({
+          opacity: 0,
+          transform: 'translateY(100%)'
+        }))
+      ])
+    ])
+  ]
+})
+export class ComposeMessageComponent {
+  @HostBinding('@routeAnimation') get routeAnimation() {
+    return true;
+  }
+
+  @HostBinding('style.display') get display() {
+    return 'block';
+  }
+
+  @HostBinding('style.position') get position() {
+    return 'absolute';
+  }
+
+  details: string;
+  sending: boolean = false;
+
+  constructor(private router: Router) {}
+
+  send() {
+    this.sending = true;
+    this.details = 'Sending Message...';
+
+    Observable.of(true)
+      .delay(1000)
+      .do(() => {
+        this.sending = false;
+
+        // Close the modal
+        this.closeModal();
+      }).subscribe();
+  }
+
+  closeModal() {
+    // Providing a `null` value to the named outlet
+    // clears the contents of the named outlet
+    this.router.navigate([{ outlets: { modal: null }}]);
+  }
+
+  cancel() {
+    // Close the modal
+    this.closeModal();
+  }
+}

public/docs/ts/latest/guide/router.jade

@@ -47,6 +47,7 @@ include ../../../_includes/_see-addr-bar
   * refactoring routing into a [routing module](#routing-module)
   * add [child routes](#child-routing-component) under a feature section
   * [grouping child routes](#component-less-route) without a component
+  * displaying [multiple routes](#named-outlets) in separate outlets
   * [redirecting](#redirect) from one route to another
   * confirming or canceling navigation with [guards](#guards)
     * [CanActivate](#can-activate-guard) to prevent navigation to a route
@@ -473,7 +474,7 @@ a#router-outlet
 .l-sub-section
   :marked
     A template may hold exactly one ***unnamed*** `<router-outlet>`.
-    The router supports multiple *named* outlets, a feature we'll cover in future.
+    The router supports multiple [named outlets](#named-outlets), covered later in the chapter.
 
 a#router-link
 :marked
@@ -1313,7 +1314,7 @@ h3#merge-hero-routes Import hero module into AppModule
    router/ts/app/heroes/hero.service.ts,
    router/ts/app/heroes/heroes.module.ts,
    router/ts/app/heroes/heroes-routing.module.ts`,
-   null,
+   'null,null,v3,null,null,null,null,null',
   `app.component.ts,
   app.module.ts,
   app-routing.module.ts,
@@ -1353,6 +1354,8 @@ h3#merge-hero-routes Import hero module into AppModule
 
   * The router should block access to certain features until the user logs-in.
 
+  * The application should display multiple routes indepdently of each other.
+
   * Changes to a feature module such as *Crisis Center* shouldn't provoke changes to the `AppModule` or
   any other feature's component.
   We need to [*separate our concerns*](https://blog.8thlight.com/uncle-bob/2014/05/08/SingleReponsibilityPrinciple.html).
@@ -1478,7 +1481,7 @@ h3#import-crisis-module Import crisis center module into the AppModule routes
   are now being provided by our `HeroesModule` and our `CrisisCenter` feature modules. We'll keep our `app-routing.module.ts` file
   for general routes which we'll cover later in the chapter.
 
-+makeExcerpt('app/app-routing.module.3.ts (v3)', '')
++makeExcerpt('app/app-routing.module.3.ts (v3)', 'v3')
 
 a#redirect
 :marked
@@ -1603,6 +1606,103 @@ h2#relative-navigation Relative Navigation
 
 +makeExcerpt('app/crisis-center/crisis-list.component.1.ts (relative routerLink)', 'relative-navigation-router-link')
 
+<a id="secondary-routes"></a>
+.l-main-section
+h3#named-outlets Displaying Multiple Routes: Named Outlets and Secondary Routes
+:marked
+  Up until now, we've used a single outlet and we've nested child routes under that outlet to group routes together.
+  The `Router` supports one primary `unnamed` outlet, but we can display multiple routes together, each displaying their own component
+  using one or more **named outlets**.
+
+  These named outlets are used to display **secondary routes**, which are configured the same way as a primary route, but
+  are independent of each other and can work in combination with each other routes. By using named outlets with secondary routes,
+  we can display multiple route components simultaneously. Secondary routes can also have their own child routes. This allows us to reflect the state of multiple
+  views in our application using the browser URL.
+
+  In our application, we want to give our users a way to contact the `Crisis Center` displayed through a modal. We also want this modal
+  to be displayed even when switching between pages in our application. We'll use a named outlet to display the modal and control its lifecycle
+  alongside our currently displayed route.
+
+  We'll create a new route component named `ComposeMessageComponent` in `app/compose-message.component.ts` to display our modal view the users will
+  use to contact the `Crisis Center`. We'll display a simple form to enter a message and a use an `Observable` to simulate a delay to handle the modal after
+  sending the message.
+
++makeExcerpt('app/compose-message.component.1.ts (compose message component)', 'v1')
+
+:marked
+  We'll add a `compose` route to our `AppRoutingModule`, using a route `path` and `component`. In order to use a named outlet, we add an additional property
+  to our route configuration called **outlet**. This outlet matches the name given to our `RouterOutlet` where we are going to to display the component. The `Router`
+  will place each route next to its intended `RouterOutlet` during the navigation process.
+
++makeExcerpt('app/app-routing.module.3.ts (compose route)', '')
+
+:marked
+  As with our other components, the `ComposeMessageComponent` is imported and added to our `AppModule`'s declarations.
+
++makeExcerpt('app/app.module.5.ts (compose component)', '')
+
+:marked
+  As we did in our initial template, we'll add a `RouterOutlet` with an additional **name** attribute and provide our named **modal** outlet. This matches the
+  name of the `outlet` we used in our `AppRoutingModule`.
+
++makeExcerpt('app/app.component.4.ts (named outlet)', '')
+
+:marked
+  Now we have two independent `RouterOutlet`s to display our routes. Routes without a specified `outlet` will use our primary `unnamed` outlet. Our `compose` outlet
+  will display our `ComposeMessageComponent`. Secondary routes are also reflected in our URL surrounded by parenthesis but are are seamlessly
+  handled by the `Router` across browsers the same way it handles [route parameters with matrix notation](#optional-route-parameters). We can visit any primary route in our application
+  and have our `compose` route displayed in combination with the primary route. An example URL displaying the `Crisis Center` list and `Compose` modal is displayed below.
+
+.l-sub-section
+  :marked
+    http://localhost:3000/crisis-center(modal:compose)
+
+:marked
+  If we break down the URL, we see the following parts.
+  * The primary route with the `crisis-center` path
+  * The parenthesis where our secondary route grouping starts and ends
+  * The name of the outlet (`modal`) split by a `colon` and followed with the secondary route path `compose`
+
+  Secondary routes are not limited to top level routes. Each level in our route configuration can contain a primary route in an unnamed outlet,
+  followed by any number of secondary routes displayed in named outlets. Secondary routes have all the same features of a primary route, including
+  access to their own [activated route](#activated-route).
+
+h3#secondary-route-navigation <i>Secondary Route Navigation</i>: merging routes during navigation
+:marked
+  We learned how the `Router` handles incoming URLs for secondary routes, but we can also navigate declaratively and imperatively using secondary routes
+  in the [link parameters array](#link-parameters-array). Let's update our application to display our `compose` route using `RouterLink` and navigating
+  away from a secondary route using the `Router` service.
+
+  The `Link Parameters Array` supports secondary routes with an object as the last index in our array. This object uses an **outlets** that lets us build
+  our links including secondary outlets in the same way we build more dynamic router links. We'll add a `Contact` link to our `Crisis Center` menu to display our
+  secondary route.
+
++makeExcerpt('app/app.component.ts (contact)', '')
+
+:marked
+  The `outlets` property within our object contains the named outlets that will be updated during the navigation process. We'll add a key for the `modal` outlet
+  and the value for the outlet is the same link parameters array we use with primary routes. When using a `RouterLink` or navigating imperatively, the `Router`
+  will **merge** the current URL with our provided secondary route. As we navigate around our application, the `Contact` link will be updated with the current URL
+  and the secondary `(modal:compose)` route, so that we can open our `compose` route independently of our currently displayed route. Once we visit the secondary route,
+  it will be merged with the current URL across each navigation as long as they're under the same parent path.
+
+.l-sub-section
+  :marked
+    When using router's `navigateByUrl` method, secondary routes will **not** be merged into the current URL and will need to be explicitly
+    provided.
+
+:marked
+  #### Clearing Secondary Routes
+  Secondary outlets persist across navigation under the same parent route. We can also remove secondary outlets using a `RouterLink` or imperatively
+  with the `Router` service using the [link parameters array](#link-parameters-array). We'll update our `ComposeMessageComponent` to remove the
+  secondary `compose` route when our user cancels the message or its sent successfully.
+
+  We'll add a `closeModal` method to our `ComposeMessageComponent` that navigates imperatively using the `router.navigate` method. Since we only want to modify the
+  secondary route, we only need to provide the secondary route object and `null` out the `modal` outlet. This will remove the secondary route from named `modal` `RouterOutlet`
+  and update the current URL.
+
++makeExcerpt('app/compose-message.component.ts (remove secondary route)', '')
+
 <a id="guards"></a>
 .l-main-section
 h2#guards Route Guards